scripts/kvm

   1 #!/bin/sh
   2 # kvm init script              Takes care for all VMM tasks
   3 #
   4 # chkconfig: - 99 01
   5 # description: The KVM is a kernel level Virtual Machine Monitor.  \
   6 #              Currently it starts a bridge and attached eth0 for it
   7
   8 dir=$(dirname "$0")
   9
  10 ifnum=${ifnum:-$(ip route list | awk '/^default / { print $NF }' | sed 's/^[^0-9]*//')}
  11 ifnum=${ifnum:-0}
  12 switch=${sw0:-sw${ifnum}}
  13 pif=${pif:-eth${ifnum}}
  14 antispoof=${antispoof:-no}
  15 command=$1
  16
  17 if [ -f /etc/sysconfig/network-scripts/network-functions ]; then
  18     . /etc/sysconfig/network-scripts/network-functions
  19 fi
  20
  21 #check for bonding link aggregation
  22 bond_int=$(awk < /etc/sysconfig/network-scripts/ifcfg-${pif} '/^MASTER=/ { print $BF }' | sed 's/MASTER=//')
  23 if [ ${bond_int}"0" != "0" ]; then
  24         pif=${bond_int}
  25 fi
  26
  27 if [ -f /etc/sysconfig/network-scripts/ifcfg-${pif} ]; then
  28     . /etc/sysconfig/network-scripts/ifcfg-${pif}
  29 fi
  30
  31 get_ip_info() {
  32     addr=`ip addr show dev $1 | egrep '^ *inet' | sed -e 's/ *inet //' -e 's/ .*//'`
  33     gateway=$(ip route list | awk '/^default / { print $3 }')
  34     broadcast=$(/sbin/ip addr show dev $1 | grep inet | awk '/brd / { print $4 }')
  35 }
  36
  37 #When a bonding device link goes down, its slave interfaces
  38 #are getting detached so they should be re-added
  39 bond_link_up () {
  40     dev=$1
  41     is_bonding=$(echo ${dev} | awk '/^bond/ { print $NF }')
  42     if [ ${is_bonding}"0" != "0" ]; then
  43         for slave in `awk < /proc/net/bonding/bond0 '/Slave Interface: / {print $3 }'`; do
  44                 ifenslave $dev $slave
  45         done
  46     fi
  47 }
  48
  49
  50 do_ifup() {
  51      if [ ${addr} ] ; then
  52         ip addr flush $1
  53         bond_link_up $1
  54         ip addr add ${addr} broadcast ${broadcast} dev $1
  55         ip link set dev $1 up
  56      fi
  57 }
  58
  59 link_exists()
  60 {
  61     if ip link show "$1" >/dev/null 2>/dev/null
  62     then
  63         return 0
  64     else
  65         return 1
  66     fi
  67 }
  68
  69 create_switch () {
  70     local switch=$1
  71
  72     if [ ! -e "/sys/class/net/${switch}/bridge" ]; then
  73         brctl addbr ${switch} >/dev/null 2>&1
  74         brctl stp ${switch} off >/dev/null 2>&1
  75         brctl setfd ${switch} 0.1 >/dev/null 2>&1
  76     fi
  77     ip link set ${switch} up >/dev/null 2>&1
  78 }
  79
  80
  81 add_to_switch () {
  82     local switch=$1
  83     local dev=$2
  84
  85     if [ ! -e "/sys/class/net/${switch}/brif/${dev}" ]; then
  86         brctl addif ${switch} ${dev} >/dev/null 2>&1
  87     fi
  88
  89     ip link set ${dev} up >/dev/null 2>&1
  90 }
  91
  92 #taken from Xen
  93 transfer_routes () {
  94     local src=$1
  95     local dst=$2
  96     # List all routes and grep the ones with $src in.
  97     # Stick 'ip route del' on the front to delete.
  98     # Change $src to $dst and use 'ip route add' to add.
  99     ip route list | sed -ne "
 100 /dev ${src}\( \|$\)/ {
 101   h
 102   s/^/ip route del /
 103   P
 104   g
 105   s/${src}/${dst}/
 106   s/^/ip route add /
 107   P
 108   d
 109 }" | sh -e
 110 }
 111
 112
 113 change_ips() {
 114     local src=$1
 115     local dst=$2
 116
 117     #take care also for case we do not have /etc/sysconfig data (the switch as a src case)
 118     if [ -x $BOOTPROTO ]; then
 119         if [ -x $(pgrep dhclient) ];then
 120            BOOTPROTO="null"
 121         else
 122             BOOTPROTO="dhcp"
 123         fi
 124     fi
 125
 126     if [ $BOOTPROTO = "dhcp" ]; then
 127         ifdown ${src} >/dev/null 2>&1 || true
 128         ip link set ${src} up >/dev/null 2>&1
 129         bond_link_up ${src}
 130         pkill dhclient >/dev/null 2>&1
 131         for ((i=0;i<3;i++)); do
 132             pgrep dhclient >/dev/null 2>&1 || i=4
 133             sleep 1
 134         done
 135         dhclient ${dst} >/dev/null 2>&1
 136     else
 137         get_ip_info ${src}
 138         ifconfig ${src} 0.0.0.0
 139         do_ifup ${dst}
 140         transfer_routes ${src} ${dst}
 141         ip route add default via ${gateway} dev ${dst}
 142     fi
 143 }
 144
 145 antispoofing () {
 146     iptables -P FORWARD DROP >/dev/null 2>&1
 147     iptables -F FORWARD >/dev/null 2>&1
 148     iptables -A FORWARD -m physdev --physdev-in ${dev} -j ACCEPT >/dev/null 2>&1
 149 }
 150
 151 status () {
 152     local dev=$1
 153     local sw=$2
 154
 155     echo '============================================================'
 156     ip addr show ${dev}
 157     ip addr show ${sw}
 158     echo ' '
 159     brctl show ${sw}
 160     echo ' '
 161     ip route list
 162     echo ' '
 163     route -n
 164     echo '============================================================'
 165     gateway=$(ip route list | awk '/^default / { print $3 }')
 166     ping -c 1 ${gateway} || true
 167     echo '============================================================'
 168 }
 169
 170 start () {
 171     if [ "${switch}" = "null" ] ; then
 172         return
 173     fi
 174
 175     create_switch ${switch}
 176     add_to_switch ${switch} ${pif}
 177     change_ips ${pif} ${switch}
 178
 179     if [ ${antispoof} = 'yes' ] ; then
 180         antispoofing
 181     fi
 182
 183     grep -q GenuineIntel /proc/cpuinfo && /sbin/modprobe kvm-intel
 184     grep -q AuthenticAMD /proc/cpuinfo && /sbin/modprobe kvm-amd
 185 }
 186
 187 stop () {
 188     if [ "${switch}" = "null" ]; then
 189         return
 190     fi
 191     if ! link_exists "$switch"; then
 192         return
 193     fi
 194
 195     change_ips ${switch} ${pif}
 196     ip link set ${switch} down
 197     brctl delbr ${switch}
 198
 199     grep -q GenuineIntel /proc/cpuinfo && /sbin/modprobe -r kvm-intel
 200     grep -q AuthenticAMD /proc/cpuinfo && /sbin/modprobe -r kvm-amd
 201     /sbin/modprobe -r kvm
 202 }
 203
 204
 205 case "$command" in
 206     start)
 207         echo -n $"Starting KVM: "
 208         start
 209         echo
 210         ;;
 211
 212     stop)
 213         echo -n $"Shutting down KVM: "
 214         stop
 215         echo
 216         ;;
 217
 218     status)
 219         status ${pif} ${switch}
 220         ;;
 221
 222     *)
 223         echo "Unknown command: $command" >&2
 224         echo 'Valid commands are: start, stop, status' >&2
 225         exit 1
 226 esac